tweak -- less pattern match for mutable data structure

Author: bobzhang

jscomp/others/belt_internalAVLset.ml

@@ -80,25 +80,21 @@ let bal l v r =
   let hl = match l with None -> 0 | Some n -> n.height in
   let hr = match r with None -> 0 | Some n -> n.height in
   if hl > hr + 2 then begin
-    (* [l] could not be None *)
     match l with None -> assert false
     | Some {left = ll; value = lv; right = lr} ->
     if heightGe ll  lr then
       create ll lv (create lr v r)
     else begin
-      (* [lr] could not be None*)
       match lr with None -> assert false 
       | Some lr -> 
       create (create ll lv lr.left) lr.value (create lr.right v r)
     end
   end else if hr > hl + 2 then begin
-    (* [r] could not be None *)
     match r with None -> assert false
     | Some {left = rl; value = rv; right = rr} ->
     if heightGe rr  rl then
       create (create l v rl) rv rr
     else begin
-      (* [rl] could not be None *)
       match rl with None -> assert false 
       | Some rl -> 
       create (create l v rl.left) rl.value (create rl.right rv rr)
@@ -140,10 +136,9 @@ let maxUndefined n =
   | Some n -> Js.Undefined.return (max0Aux n)
 
 let rec removeMinAuxWithRef n v =
-  let {left = ln; right = rn; value = kn} = n  in
-  match ln with
-  | None ->  v.contents<- kn ; rn
-  | Some ln -> bal (removeMinAuxWithRef ln v) kn rn
+  match n.left with
+  | None ->  v.contents<- n.value ; n.right
+  | Some ln -> bal (removeMinAuxWithRef ln v) n.value n.right
 
 
 

lib/es6/belt_internalAVLset.js

@@ -141,14 +141,12 @@ function maxUndefined(n) {
 }
 
 function removeMinAuxWithRef(n, v) {
-  var kn = n.value;
   var ln = n.left;
-  var rn = n.right;
   if (ln !== undefined) {
-    return bal(removeMinAuxWithRef(ln, v), kn, rn);
+    return bal(removeMinAuxWithRef(ln, v), n.value, n.right);
   } else {
-    v.contents = kn;
-    return rn;
+    v.contents = n.value;
+    return n.right;
   }
 }
 
@@ -374,7 +372,7 @@ function checkInvariantInternal(_v) {
     var r = v.right;
     var diff = treeHeight(l) - treeHeight(r) | 0;
     if (!(diff <= 2 && diff >= -2)) {
-      throw new Error("File \"belt_internalAVLset.ml\", line 299, characters 6-12");
+      throw new Error("File \"belt_internalAVLset.ml\", line 294, characters 6-12");
     }
     checkInvariantInternal(l);
     _v = r;

lib/js/belt_internalAVLset.js

@@ -141,14 +141,12 @@ function maxUndefined(n) {
 }
 
 function removeMinAuxWithRef(n, v) {
-  var kn = n.value;
   var ln = n.left;
-  var rn = n.right;
   if (ln !== undefined) {
-    return bal(removeMinAuxWithRef(ln, v), kn, rn);
+    return bal(removeMinAuxWithRef(ln, v), n.value, n.right);
   } else {
-    v.contents = kn;
-    return rn;
+    v.contents = n.value;
+    return n.right;
   }
 }
 
@@ -374,7 +372,7 @@ function checkInvariantInternal(_v) {
     var r = v.right;
     var diff = treeHeight(l) - treeHeight(r) | 0;
     if (!(diff <= 2 && diff >= -2)) {
-      throw new Error("File \"belt_internalAVLset.ml\", line 299, characters 6-12");
+      throw new Error("File \"belt_internalAVLset.ml\", line 294, characters 6-12");
     }
     checkInvariantInternal(l);
     _v = r;